Alkoxyalkylamine salts of alkylaryl sulfonic acids



?atented Mar. 23, 1954 ALKOXYALKYLAMINE SALTS F ALKYL- ARYL SULFONIC ACIDS Vincent J. Keenan,

8 Claims.

This invention relates to new amine salts of alkylaryl sulfonic acids having excellent wetting, foam, and cletergency characteristics, and relates more particularly to v-alkoxypropylamine salts of alkylaryl sulfonic acids, the alkyl group of such acids containing from. 9 to carbon atoms and preferably an average of 12 carbon atoms. Such compounds have excellent utility in dishwashing.

It is an object of this invention to provide new liquid detergent compound particularly suitable for household use and characterized by improved detergency and also good foam stability.

We have discovered that the -alkoxypropylamine salts of alkylaryl sulfonic acids, a new group of compounds, while less soluable than some of the known liquid detergents, are markedly better detergents for proteinaceous and fatty soils and mixtures thereof. They are less irritating to the skin than the corresponding inorganic soaps. These new compounds have exceptional utility in washing dishes, not only because of their improved detergency, but 1ikewise because of their superior foaming power and foam stability. The latter is particularly important in the economical use of such detergents, since it furnishes the user with a measure of the residual detergent available in the wash solution, e. g., a dishpan, throughout the cleaning operation.

In accordance with the present invention, the new detergent compounds may be produced simply by neutralizing, or reacting a theoretical stoichiometric amount of an alkylbenzene sulfonic acid or acid mixture with a y-alkoxypropylamine.

The amines used in the production of the new compounds are the 'y-alkoxproplamines in which the alkoxy group contains from 1 to 4 carbon atoms and in which a methyl group may be substituted for a hydrogen in the beta-position. Such amines can be prepared by various known methods such, for example, as by reacting a suitable alkyl alcohol with propenenitrile, and reducing the reaction product to the corresponding amine, and many of these materials are commercially available. Specific examples of the alkoxypropylamines are: 'y-methoxypropylamine y-methoxy-B-methylpropylamine, y ethoxypropylamine, 'y-ethoxy-p-methylpropylamine, y-propoxypropylamine, 'y-propoxy 13 methylpropylamine, y-isopropoxypropylamine, -isopropoxy-fimethylpropylamine, 'y-butoxypropylamine, 'y-blltoxy-p-methylpropylamme, 7 isobutoxypropyl- Ardmore, and Frank J. Gozlow, Philadelphia, Pa., assignors to The Atlantic Refining Company, Philadelphia, Pa., a corporation of Pennsylvania No Drawing. Application March 21, 1952, Serial No. 277,916

carbon atoms. readily prepared by sulfonating appropriate 'alkylated benzene hydrocarbons or hydrocarbon amine, and -isobutoxy [3 methylpropylamine, and mixtures thereof.

The alkylarylsulfonic acids or acid mixtures which are neutralized, in accordance with this invention, to produce the new amine salts having exceptional utility in dishwashing are those obtained by sulfonation of alkylated benzenes or benzene mixtures having from 9 to 15 carbon atoms in the alkyl group, and preferably averaging about 12 carbon atoms in the alkly group. In addition to the long chain alkyl group, other nuclear hydrogen atoms of the aromatic may be substituted by alkyl groups having from 1 to 3 These sulfom'c acids may be mixtures using sulfuric acid of about 98% to 99% concentration or higher and then separating the spent sludge containing free sulfuric acid from the desired sulfonic acid by settling and decanting or other suitable methods. The resulting sulfonic acid preferably is further purified by dissolving the same in benzene, octane, or other convenient solvent and decanting or otherwise I removing the additional sludge which is thereby separated. The solvent may be removed from the sulfonic acid by evaporation or other methods either prior or subsequent to neutralization or reaction of the sulfonic acid with the alkylalkanol amine.

As previously stated, the alkyl benzene hydrocarbon or hydrocarbon mixtures which are sulfonated to provide the necessary sulfonic acids for neutralization have an alkyl group containing from 9 to 15 carbon atoms and the remaining nuclear substituents of the benzene radical are selected from the group consisting of hydrogen and lower alkyl groups having from. 1 to 3 carbon atoms. In all cases, however, the aryl hydrocarbon may be one or a mixture of two or more hydrocarbons such as benzene, toluene, xylene, ethyl benzene, propyl benzene, and isopropyl benzene.

Specific examples of the alkyl aromatic hydrocarbons herein contemplated as suitable for the invention are nonyl benzene, nonyl toluene, nonyl ethyl benzene, nonyl propyl benzene, nonyl dimethyl benzene, nonyl diethyl benzene, nonyl methyl ethyl benzene, nonyl methyl propyl benzene, nonyl ethyl propyl benzene, nonyl dipropyl benzene, decyl benzine, decyl toulene, decyl ethyl benzene, decyl propyl benzene, decyl dimethyl benzene, decyl diethyl benzene, decyl methyl ethyl benzene, decyl methyl propyl benzene, decyl ethyl propyl benzene, decyl dipropyl benzene, undecyl benzene, undecyl toluene, undecyl ethyl benzene, undecyl dimethyl benzene, undecyl diethyl benzene, undecyl methyl ethyl benzene, undecyl methyl propyl benzene, undecyl dipropyl benzene, dodecyl benzene, dodecyl toluene, vdodecyl ethyl benzene, dodecyl propyl benzene, dodecyl dimethyl benzene, dodecyl diethyl benzene, dodecyl methyl ethyl benzene, dodecyl methyl propyl benzene, dodecyl dipropyl benzene, tridecyl benzene, tridecyl toluene, tridecyl ethyl benzene, tridecyl propyl benzene, tridecyl dimethyl benzene, tridecyl diethyl benzene, tridecyl methyl ethyl benzene, tridecyl methyl propyl benzene, tridecyl dipropyl benzene, tetradecyl benzene, tetradecyl toluene, tetradecyl ethyl benzene, tetradecyl propyl benzene, tetradecyl dimethyl benzene, tetradecyl diethyl benzene, tetradecyl methyl ethyl benzene, tetradecyl methyl propyl benzene, tetradecyl dipropyl benzene, pentadecyl benzene, pentadecyl toluene,

pentadecyl ethyl benzene, pentadecyl propyl benzene, pentadecyl dimethyl benzene, pentadecyl diethyl benzene, pentadecyl methyl ethyl benzene, pentadecyl methyl propyl benzene, and pentadecyl dipropyl benzene or mixtures thereof.

The production of the alkylated benzene hydrocarbons or hydrocarbon mixtures may be accomplished by various methods such, for example,

as by reacting a chlorinated alkyl hydrocarbon or hydrocarbon mixture having 9 to carbon atoms with the aromatic hydrocarbon in the presence of a Friedel-Crafts catalyst such as A1C13. The alkyl halide may be obtained by chlorinating the proper petroleum fraction such as a kerosene fraction. The aromatic hydrocarbon may be benzene, toluene, xylene, ethyl benzene, propyl benzene, and isopropyl benzene.

Preferably, however, the benzene hydrocarbon may be alkylated with a mono-olefin polymer or mixture of polymers containing from 9 to 15 carbon atoms in the presence of a suitable catalyst such as sulfuric acid, AlCls, SnCh, ZnClz, BFs, or HF. The olefin polymer or polymer mixture is most suitably derived by subjecting a lower olefin to polymerizing conditions in the which have been fractionated to remove all or substantially all of the butane, butenes, and heavier hydrocarbons. For example, a refinery gas stream comprising 4.6 mol methane, 5.2 mol ethylene, 19.5 mol ethane, 26.2 mol propylene, and 44.5 mol propane may be contacted with a supported phosphoric acid catalyst at 300 F. to 600 F. under a pressure between 200 and 1800 p. s. i., employing a space velocity of 0.05 to 0.15 lb. mols of propylene per lb. of catalyst per hour. The resulting polymers will comprise a complex'mixture of olefinic hydrocarbons containing from 6 to about 18 carbon atoms per molecule, and these polymers will not consist solely of dimers, trimers, pentamers, etc., but Will include C7, C8, C10, C11, C13, C14, and slightly higher polymers due to the interpolymerization of propylene polymer degradation products as well a the presence, in most cases, of ethylene which may be interpolymerized. The polymer mixture may also contain. minor amounts of parafiins of various molecular weights as byproducts of the polymerization reaction. Preferred conditions for polymerization require temperatures between 300 F. and 500 F. under pressures of 300 to 1000 p. s. i. at a space velocity of about 0.004 lb. mols of propylene per lb. of phosphoric acid catalyst per hour. To obtain a preponderance of polymers averaging 9 carbon atoms, high pressures and high space velocities are desirable, i. e., 1000 to 1800 p. s. i. and 0.006 space velocity. 0n the other hand, to obtain high yields of polymers averaging 12 carbon atoms with minor amounts of polymers averaging 15 carbon atoms, somewhat lower pressures and space velocities should be used, for example, 200 to 800 p. s. i. and 0.002 to 0.004 space velocity. Depending upon the average chain length ormolecular weight of the polymers desired for the alkylation of the aryl hydrocarbon, the crude propylen polymers may be fractionally distilled to obtain the necessary fraction or fractions, and these may be either distillates or distillation residues.

A polymer fraction may be mixed, for example, with 5 to 6 molar equivalents of benzene and 0.05 to 0.1 molar equivalents ofai'catalyst such as AlCls, and the alkylation carried out at to 180 F. The catalyst then is separated from the alkylation mixture, the mixture is washed with dilute alkali solution, settled, and Washed to remove alkali. The alkylation mixture is then fractionally distilled to remove excess benzene, low boiling alkylated benzene resulting as degradation by-products, and small amounts of low boiling olefins and parafiins.

An alkylated aryl hydrocarbon mixture which is particularly useful in the present invention may be obtained by reacting the above mentioned propylene polymer fraction containing from 9 to 15 carbon atoms with an aromatic hydrocarbon and subsequently fractionating the alkylated aryl hydrocarbon mixture to obtain a fraction con- .sisting predominantly of alkyl aromatics having 12 carbon atoms in the alkyl group, or, alternatively, the propylene polymer fraction having 9 to 15 carbon atoms may be fractionated to separate a narrow boiling out consisting of a major proportion of polymers having 12 carbon atoms which may subsequently be reacted with the aromatic hydrocarbon to produce a mixture of alkylated aromatics having predominantly 12 carbon atoms in the alkyl group.

If desired, a combination of these two methods may be used, 1. e., fractionation of the C9 to .C15 propylene polymer mixture, alkylation with the C12 cut, then fractionation of the alkylated arc matic mixture. In all cases, however, thealekylated aromatic hydrocarbon mixture which is particularly useful contains a major proportion of an alkylated aromatic hydrocarbon having- 12 carbon atoms in the alkyl group with very minor amounts of alkylated aromatics having alkyl groups other than 12 carbons and within the range from 9 to 15 carbons.

The following examples are given for the purpose of further illustrating the present invention, but are not intended to be limiting on the scope thereof. The alkoxypropylamine salts produced in the examples in accordance with the present nvention were subjected either to the York dishwashing test or the accelerated dishwashing test,

as indicated. By way of comparison, the same tests were formed on a heretofore known liquid detergent, the triethanolamine salt of the same sulfonic acid, which is particularly suitable for household use because of its high water solubility and rinsability, and also on commercial powdered soaps, such as the sodium salts of fatty acids produced from cocoanut oil and tallow to show the marked superiority of the alkoxypropylamine salts for dishwashing.

The York dishwashing test was made in accordance with the procedure described by Machlis and Michaels in Soap and Sanitary Chemicals, Sept. 1948, pages 42-44. The results of such test are given in the table in terms of the percent detergency (by reflection).

The accelerated dishwashing test involves soiling 8-inch white china dishes by first applying to each dish '7 gms. of a blend of 71.5% fresh egg and 28.5% bacon grease mixed in a Waring Blendor and then drying the dishes in an oven, maintained at 150 F., for minutes. After cooling to room temperature, the dishes are washed one by one in an oval 14" by 18" by 15" dishpan containing 2000 cc. of 100 p. p. m. hard water solution having 0.15% concentration of the detergent under investigation. Prior to placing any dishes in the water solution, it is agitated violently by hand for approximately 15 seconds to build a full head of foam.

As the dishes are washed, the foam breaks down and the end point is reached when no foam remains in the dishpan. Results of the test are reported as the number of dishes, each containing originally 7 gms. of soil, cleaned before all foam disappears.

This test has proven to have a high degree of reproducibility upon repeated testing with a given detergent and among a variety of operators as well.

In each of the examples below the sulfonic acid employed was prepared, as above described, by sulfonation of a heart-cut alkylated benzene mixture containing an average of 12 carbon atoms in the alkyl group.

EXAMPLE I To a quantity of the sulfonic acid pure 'y-methoxy-propylamine was added in sufficient quantity to substantially neutralize the acid. The resulting salt was subjected to the York dishwashing test and the results thereof for 0.06% and 0.20% concentrations in 100 p. p. no. hard water are reported in Table I.

EXAMPLE II To a quantity of the sulfonlc acid 'y-isopropoxy-propylamine was added in suflicient quantity to neutralize the acid. The percent detergency, as determined by the York test, of the resulting salt is given in Table I for 0.06%, 0.20 and 0.30% concentrations in 100 p. p. m. hard water.

EXAMPLE III A quantity of the sulfonic acid was neutralized with pure triethanolamine. The resulting product was subjected to the York dishwashing test and the results thereof for 0.06%, 0.20% and 0.30% concentrations in 100 p. p. no. hard water are given in Table I.

EXAMPLE IV A commercial household soap powder consisting of the sodium salt of a fatty acid produced from cocoanut oil was subjected to the York dishwashing testusing concentrations of 0.20% and 0.30% soap in pp. m. hard water and the results are set forth in the Table I.

EXAMPLE V A commercial household soap powder consisting of the sodium salt of a fatty acid produced from tallow was subjected to the York dishwashing test using concentrations of 0.20% and 0.30% soap and the results are set forth in Table I.

Table I Percent Detergency Example No.

Soln. Soln. S0111.

The above examples and data clearly show the marked superiority in dishwashing of the alkoxypropylamine salts of alkyaryl sulfonic acids over the triethenolamine salt of the same acid and also over commercial sodium salts of fatty acids produced from cocoanut oil and tallow.

EXAMPLE VI A quantity of the sulfonic acid was neutralized with v-methoxypropylamine and the resulting salt was subjected to the accelerated dishwashing test. The results of such test are reported in Table II.

EXAMPLEVII To a quantity of the sulfonic acid was added suflicient 'y-isopropoxypropylamine to neutralize the acid. The resulting product was subjected to the accelerated dishwashing test with the results given in Table II.

EXAMPLE VIII Another portion of the sulfonic acid was neutralized with 'y-n-butoxypropylamine and the results of the accelerated dishwashing test on the product appear in Table II.

EXAMPLE IX Still another quantity of the sulfonic acid was neutralized with triethanolamine and the results of the accelerated dishwashing test on the product are presented in Table II.

Table II Example No. Dishes Washed VI 7% VII 7% VIII. 8% IX...

and such materials also possess superior detergency characteristics.

We claim:

l. A v-alkoxypropylamine salt of an alkylaryl sulfonic acid, the alkyl radical of said acid having from 9 to 15 carbon atoms and the remaining nuclear substituents of the aryl radical being selected from the group consisting of hydrogen and lower alkyl groups having from 1 to 3 carbon atoms, and said alkoxy group containing from 1 to 4 carbon atoms.

2. A v-alkoxypropylamine salt of an alkylbenzene sulfonic acid having 9 to 15 carbon atoms in the alkyl group, the alkoxy radical of the propylamine having from 1 to 4 carbon atoms and the substituents in the [3-position of the alkoxy radical being selected from the group consisting of hydrogen and methyl radical.

5. q-n-butoxypropylamine salt of an' alkylbenzene sulfonic acid having from 9 to 15 carbon atoms in the alkyl group.

6. 'y-methoxypropylamine salt of an alkylbenzene sulfonic acid having 12 carbon atoms in the alkyl group.

'7. 'y-isopropoxypropylamine salt of an alkylbenzene sulfonic acid having 12 carbon atoms in the alkyl group.

8. 'y-n-butoxypropylamine salt of an alkylbenzene sulfonic acid having 12 carbon atoms in the alkyl group.

' VINCENT J. KEENAN.

FRANK J. GOZLOW.

References Cited in thevfile of this patent UNITED STATES PATENTS Number Name Date 2,085,298 De Groote June 29, 19 37 2,226,121 De Groote Dec. 24, 1940 2,519,930 Riethof et al Aug. 22, 1950 2,572,605 Fincke Oct. 23. 1951 

1. A Y-ALKOXYPROPYLAMINE SALT OF AN ALKYLARYL SULFONIC ACID, THE ALKYL RADICAL OF SAID ACID HAVING FROM 9 TO 15 CARBON ATOMS AND THE REMAINING NUCLEAR SUBSTITUENTS OF THE ARYL RADICAL BEING SELECTED FROM THE GROUP CONSISTING OF HYDROGEN AND LOWER ALKYL GROUPS HAVING FROM 1 TO 3 CARBON ATOMS, AND SAID ALKOXY GROUP CONTAINING FROM 1 TO 4 CARBON ATOMS. 